"I heard gunshots," ABC13 video journalist Gerzain Garcia reported.
"I said, 'Let's go' and we drove closer.
"I thought they had stopped shooting," Garcia said.
Even after the last shot the men "continued to threaten and wave the guns at each other".
Eyewitness News reporter Erica Simon had taken cover, ABC13 reports.
"After the gunfire ended, she walked around the truck, only to see a woman bleeding. A bystander across the street had been struck by one of the bullets, with a graze to her head," ABC13 reports.
"We tried to comfort her as best we could, and let her know an ambulance was on its way. A good Samaritan, an EMT, was applying pressure to her head to stop the bleeding," Simon said.
The woman was treated at a nearby hospital, according to ABC13.
Police believe one of the drivers was struck in the chest, but he "continued to walk with his gun raised against the other driver".
Police quickly took both men into custody. The wounded driver was taken to Ben Taub Hospital.
Other drivers caught in the traffic found themselves trapped in the gunfire, including Annie Ranck.
"I saw one man with a gun not 20 yards from me, and he was shooting his gun in all directions. I flashed my lights at other drivers. I wanted to warn people about what was happening," Ranck told ABC13.
"It was crazy," Garcia said.
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